When the goddess Artemis disappears while hunting a rare, ancient monster, a group of her followers joins Percy and his friends in an attempt to find and rescue her before the winter solstice, when her influence is needed to sway the Olympian Council regarding the war with the Titans.

"Seventh-grader Tristan Strong tumbles into the MidPass and, with allies John Henry and Brer Rabbit, must entice the god Anansi to come out of hiding and seal the hole Tristan accidentally ripped in the sky."--

In order to steal the Midnight Drum and free her powerful grandmother, twelve-year-old vampire Serwa deceptively collaborates with her rival Declan, a Slayer, but joining forces compels Serwa to confront truths about herself she has tried hard to deny.